The HT1376 cell line, originating from a grade 3 carcinoma of the urinary bladder, presents a near-tetraploid karyotype, depicting TP53, RB1 and PTEN losses (yet no alteration of the PIK3CA gene region) [49], which is compatible with an invasive and metastatic profile [50]. The gene discussed is RB1; the disease is urinary bladder carcinoma.